How early can I know if a brew is ruined?

Question

Today I tried my very first brew using a Coopers DIY kit. I was told the Lager mix that comes with the kit probably won't taste amazing, but it should be hardy and forgiving for beginners that don't have a temperature controlled fridge yet.

The instructions recommend making sure the water temperature is between 21-27 degrees celcius before adding yeast. But it also said to add the yeast ASAP after mixing. So, stupidly, I didn't do a wet run and didn't have any (properly) cold water and as a result my mix was at 36 degrees when I added the yeast! Even now, an hour later I think it's at about 34 degrees.

So, instead of bottling in a few days then waiting a month to find out if it's ruined, I was considering scrapping this batch and trying again (with a wet run first to get the temperature right this time). So my question is: will tasting it in a few days be sufficient to tell if I need to start again? How exactly will I know?

My Original Gravity measured at 38, but I don't know if that's relevant.

Note I've looked at this question which is similar to mine, but a bit of a different issue: I think I ruined my first brew

Thanks in advance for any advice. I'm really looking forward to my first good batch :) Then, once I have a proper fridge I would love to try some more adventurous recipes.

Answer 1

I would get hold of another sachet of yeast as a backup. If you have a local homebrew store, almost any type of yeast will work for this kit, but I'd recommend Safale US-05 if you can get that, since that will give you a cleaner profile. If they have liquid yeasts, then Wyeast 1056 or White Labs WLP001 will produce equivalent results. Once you've got hold of a new stock of yeast, simply pitch it when the batch has cooled to room temperature.

So, why do you need a new sachet of yeast? 36 C is a very high pitching temperature. It's questionable if the yeast will survive that - it is dependent on the specific strain of yeast - some will, others won't - so the yeast may have not survived the pitch. Even if it did survive, you will certainly taste the high pitching temperature it in the beer - it will get a hot alcohol taste like bad whiskey.

Pitching a new sachet of yeast when the temperature is down to the recommended range will both ensure that there is yeast available (if the first pitch didn't survive) plus ensure there is yeast fermenting at recommended temperature, which will reduce the amount of hot alcohols and esters produced.

If you do this, then taste after a week then you'll know if the batch was affected in any way - among other flavors it will taste fruity and/or like bad spirits. But even if you don't like the taste, I recommend you keep hold of the batch. After a week, the beer will still be very green, and it takes a few batches to become familiar with how that tastes. In your shoes, I'd leave the beer at least a couple of weeks before deciding if you are prepared to bottle or not, and I would probably go ahead and bottle even if it didn't taste great. This will give you a practice run with bottling/carbonation, and you may even be surprised at the results after 4-5 weeks - time can be a wonderful healer when it comes to fixing beer!

To sum up:

• get some more yeast, and pitch at room temperature
• take a gravity sample taste after a week
• repeat again after two weeks, and then bottle
• taste bottle at 4 weeks (2 weeks after bottling)